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Early and accurate detection of infection by pathogenic microorganisms, such as Plasmodium, the causative agent of malaria, is critical for clinical diagnosis and ultimately determines the patient's outcome. We have combined a polystyrene-based microfluidic device with an immunoassay which utilises Surface-Enhanced Raman Spectroscopy (SERS) to detect malaria. The method can be easily translated to a point-of-care testing format and shows excellent sensitivity and specificity, when compared to the gold standard for laboratorial detection of Plasmodium infections. The device can be fabricated in less than 30 min by direct patterning on shrinkable polystyrene sheets of adaptable three-dimensional microfluidic chips. To validate the microfluidic system, samples of P. falciparum-infected red blood cell cultures were used. The SERS-based immunoassay enabled the detection of 0.0012 ± 0.0001% parasitaemia in a P. falciparum-infected red blood cell culture supernatant, an ∼7-fold higher sensitivity than that attained by most rapid diagnostic tests. Our approach successfully overcomes the main challenges of the current Plasmodium detection methods, including increased reproducibility, sensitivity, and specificity. Furthermore, our system can be easily adapted for detection of other pathogens and has excellent properties for early diagnosis of infectious diseases, a decisive step towards lowering their high burden on healthcare systems worldwide. [ABSTRACT FROM AUTHOR]

Droplet-based microfluidic technology is a powerful tool for generating large numbers of monodispersed nanoliter-sized droplets for ultra-high throughput screening of molecules or single cells. Yet further progress in the development of methods for the real-time detection and measurement of passing droplets is needed for achieving fully automated systems and ultimately scalability. Existing droplet monitoring technologies are either difficult to implement by non-experts or require complex experimentation setups. Moreover, commercially available monitoring equipment is expensive and therefore limited to a few laboratories worldwide. In this work, we validated for the first time an easy-to-use, open-source Bonsai visual programming language to accurately measure in real-time droplets generated in a microfluidic device. With this method, droplets are found and characterized from bright-field images with high processing speed. We used off-the-shelf components to achieve an optical system that allows sensitive image-based, label-free, and cost-effective monitoring. As a test of its use we present the results, in terms of droplet radius, circulation speed and production frequency, of our method and compared its performance with that of the widely-used ImageJ software. Moreover, we show that similar results are obtained regardless of the degree of expertise. Finally, our goal is to provide a robust, simple to integrate, and user-friendly tool for monitoring droplets, capable of helping researchers to get started in the laboratory immediately, even without programming experience, enabling analysis and reporting of droplet data in real-time and closed-loop experiments. [ABSTRACT FROM AUTHOR]

Solution-based memristors are emergent devices, due to their potential in electrical performance for neuromorphic computing combined with simple and cheap fabrication processes. However, to achieve practical application in crossbar design tens to hundreds of uniform memristors are required. Regarding this, the production step optimization should be considered as the main objective to achieve high performance devices. In this work, solution-based indium gallium zinc oxide (IGZO) memristor devices are produced using a combustion synthesis process. The performance of the device is optimized by using different annealing temperatures and active layer thicknesses to reach a higher reproducibility and stability. All IGZO memristors show a low operating voltage, good endurance, and retention up to 105 s under air conditions. The optimized devices can be programmed in a multi-level cell operation mode, with 8 different resistive states. Also, preliminary results reveal synaptic behavior by replicating the plasticity of a synaptic junction through potentiation and depression; this is a significant step towards low-cost processes and large-scale compatibility of neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

The development of robust and sensitive point-of-care testing platforms is necessary to improve patient care and outcomes. Surface-enhanced Raman scattering (SERS)-based immunosensors are especially suited for this purpose. Here, we present a highly sensitive and selective SERS immunoassay, demonstrating for example the detection of horseradish peroxidase (HRP), in a sandwich format. The strength of our biosensor lies in merging: (i) SERS-immunotags based on gold nanostars, allowing exceptional intense SERS from attached Raman probes, covalent attachment of anti-HRP antibodies by a simple chemical method providing exceptional antigen binding activity; (ii) the ease of preparation of the capture platform from a regenerated cellulose-based hydrogel, a transparent material, ideal for microfluidics applications, with low background fluorescence and Raman signal, particularly suited for preserving high activity of the covalently bound anti-HRP antibodies. The sandwich complexes formed were characterised by atomic force microscopy, and by scanning electron microscopy coupled with electron diffraction spectroscopy; and (iii) the robustness of the simple Classical Least Squares method for SERS data analysis, resulting in superior discrimination of SERS signals from the background and much better data fitting, compared to the commonly used peak integral method. Our SERS immunoassay greatly improves the detection limits of traditional enzyme-linked immunosorbent assay approaches, and its performance is better or comparable to those of existing SERS-based immunosensors. Our approach successfully overcomes the main challenges of application at point-of-care, including increasing reproducibility, sensitivity, and specificity, associated with an environmentally friendly and robust design. Also, the proposed design withstands several cycles of regeneration, a feature absent in paper-SERS immunoassays and this opens the way for sensitive multiplexing applications on a microfluidic platform. [ABSTRACT FROM AUTHOR]

Resistive switching (RS) devices or memristors have received a lot of attention in the last decade owing to their valuable and interesting properties, such as high-density, switching speed and scalability. Printed techniques are an emergent technology that allows the large-scale production of these devices through direct patterning which decreases the associated costs and provides a more viable process. However, some significant challenges remain to be solved in terms of thermal budget to improve the electrical performance and grant their compatibility with the printing industry. In this work, for the first time, printed combustion-based aluminium oxide (AlOx) RS devices are produced via inkjet printing at low temperature by the combination of thermal annealing (150 °C) and deep ultraviolet (DUV) treatment. These devices present a bipolar resistive switching behaviour with good endurance, high reproducibility (95%) and retention time (105 s), and sufficient ON/OFF ratio to achieve a multilevel cell (MLC) with up to 4 states. The obtained results help to understand the electrical characteristics of printed metal oxide RS devices processed at low temperatures and showcase their potential for hardware security applications. [ABSTRACT FROM AUTHOR]

Solution processing of amorphous metal oxides using excimer laser annealing (ELA) has been lately used as a viable option to implement large-area electronics, offering high quality materials at a reduced associated cost and process time. However, the research has been focused on semiconductor and transparent conductive oxide layers rather than on the insulator layer. In this work we present amorphous aluminum oxide (AlOx) thin films produced at low temperature (≤150 °C) via combustion synthesis triggered by ELA, for oxide thin film transistors (TFTs) suitable for manufacturing flexible electronics. The study showed that combining ELA and combustion synthesis leads to an improvement in the dielectric thin film's densification in a shorter time (≤15 min). Optimized dielectric layers were obtained combining a short drying cycle at 150 °C followed by ELA treatment. High breakdown voltage (4 MV cm−1) and optimal dielectric constant (9) was attained. In general, TFT devices comprising the AlOx fabricated with a drying cycle of 15 min followed by ELA presented great TFT properties, a high saturation mobility (20.4 ± 0.9 cm2 V−1 s−1), a small subthreshold slope (0.10 ± 0.01 V dec−1) and a turn-on voltage ∼0 V. ELA is shown to provide excellent quality solution-based high-κ AlOx dielectric, that surpass other methods, like hot plate annealing and deep ultraviolet (DUV) curing. The results achieved are promising and expected to be of high value to the printed electronic industry due to the ultra-fast film densification and the surface/area selective nature of ELA. [ABSTRACT FROM AUTHOR]

Solution processing of metal oxides has been the focal point of interest for many researchers mainly because of the cost effectiveness and improved properties of metal oxides. However, achieving uniform and high-quality film deposition has been a recurring challenge using various wet-chemical techniques. Herein, we report a fully solution-based fabrication process exploiting both the ultrasonic spray pyrolysis (USP) and spin coating techniques owing to their simplicity, high degree of freedom for mixing metal oxide precursor salt, and larger area deposition. An amorphous zirconium oxide (ZrOx) dielectric and zinc tin oxide (ZTO) semiconductor were deposited, respectively. The dielectric characteristics of the ZrOx thin films were accessed by fabricating MIS-devices for the samples deposited at 200 °C and 400 °C, which exhibited a capacitance of 0.35 and 0.67 μF cm−2 at 100 kHz and relative permittivity of 8.5 and 22.7, respectively. The ZrOx thin film was then integrated as the gate dielectric layer in ZTO solution-processed thin film transistors, exhibiting a high electrical performance with low hysteresis (−0.18 V), high on/off current ratio of 106 orders of magnitude, saturation mobility of 4.6 cm2 V s−1, subthreshold slope of 0.25 V dec−1, and operating at a low voltage window of 3 V. Based on these results, the as-fabricated ZTO/ZrOx TFT opens the potential application of solution-processed transistors for low-cost electronic devices. [ABSTRACT FROM AUTHOR]

Energy conversion by the surface plasmon effect is considered a promising alternative to an effective transformation of solar energy in photovoltaic devices through the generation of hot electrons in plasmonic nanostructures. Here, we report the direct visualization of the space charge potential profile across the cross-section of perovskite solar cells before and after plasmonic treatment and the nanoscale photoresponses of perovskite thin films to gain key insights into the fundamental mechanism of the charge carrier dynamics inside the cells during operation. Understanding the charge transport dynamics inside the solar cells is important for identifying the basic processes of the photovoltaic mechanism. Plasmon resonances in metal nanostructures and the accelerated charge transfer improved the overall performances of the solar cells. The recorded photocurrent images reveal an enhanced photo-response at the nanoscale for the plasmonic solar cells due to hot electron generation in Au nanoparticles. In addition, the potential-profiling results also indicate enhanced charge separation in the plasmon-based solar cells, which is associated with the better performances of the devices. The results represent a new feature for plasmonic nanostructures in photovoltaics, which could lead to the tuning of the carrier transfer dynamics inside the cells. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic joint inflammation and one of the main causes of chronic disability worldwide with high prevalence in the ageing population. RA is characterized by autoantibody production, synovial inflammation and bone destruction, and the most accepted biomarker is rheumatoid factor (RF) autoantibodies. In this work, we developed a low-cost approach for the detection and quantification of the RF marker. This colorimetric immunosensor is based on gold nanoprobe crosslinking that results in extensive aggregation in the presence of the pentameric IgM RF. Aggregation of the nanoconjugates yields a color change from red to purple that can be easily observed by the naked eye. The interaction between nanoconjugates and the specific target was confirmed via dynamic light scattering (DLS), Raman spectroscopy and atomic force microscopy (AFM) imaging. This conceptual system shows a LOD of 4.15 UA mL−1 IgM RF (clinical threshold is set for 20 IU mL−1). The one-step biosensor strategy herein proposed is much faster than conventional detection techniques, without the need for secondary antibodies, additional complex washing or signal amplification protocols. To the best of our knowledge this is the first report on target induced aggregation of gold nanoprobes for quantitative colorimetric autoantibody detection. [ABSTRACT FROM AUTHOR]

Photonic microstructures placed at the topside of photovoltaic cells are currently one of the preferred light management solutions to obtain efficiency enhancement due to the increment of the optical absorption produced in the active medium of the devices. Herein, we present the results concerning a practical, low-cost and scalable approach to integrate metal-oxide based light trapping microstructures on the front contact of amorphous silicon thin film solar cells. A colloidal lithography method was used to pattern the wavelength-sized pyramidal-like features composing the structures, made of two different transparent materials, TiO2 and IZO, allowing the detailed study of the influence of their geometrical parameters on the optoelectronic properties of the devices. These top coating structures are deposited as a post-process after the solar cell fabrication, thus facilitating and broadening their industrial applicability. Measurements of the light absorption, external quantum efficiency and I–V curves revealed that the structured coatings provide strong broadband improvements in the generated current, due to the suppression of reflected light at short wavelengths and the increment of the optical path length of the longer wavelengths (via light scattering), within the amorphous silicon layer. As a result, in the four types of structures analyzed in this study, remarkable increments were achieved in the cells’ efficiencies (up to 14.4%) and generated currents (up to 21.5%), with respect to the flat reference cells. [ABSTRACT FROM AUTHOR]

A novel generation of flexible opto-electronic smart applications is now emerging, incorporating photovoltaic and sensing devices driven by the desire to extend and integrate such technologies into a broad range of low cost and disposable consumer products of our everyday life and as a tool to bring together the digital and physical worlds. Several flexible polymeric materials are now under investigation to be used as mechanical supports for such applications. Among them, cellulose, the most abundant organic polymer on the Earth, commonly used in the form of paper, has attracted much research interest due to the advantages of being recyclable, flexible, lightweight, biocompatible and extremely low-cost, when compared to other materials. Cellulose substrates can be found in many forms, from the traditional micro-cellulose paper used for writing, printing and food/beverage packaging (e.g. liquid packaging cardboard), to the nano-cellulose paper which has distinct structural, optical, thermal and mechanical properties that can be tailored to its end use. The present article reviews the state-of-the-art related to the integration and optimization of photonic structures and light harvesting technologies on paper-based platforms, for applications such as Surface Enhanced Raman Scattering (SERS), supporting remarkable 107 signal enhancement, and photovoltaic solar cells reaching ∼5% efficiency, for power supply in standalone applications. Such paper-supported technologies are now possible due to innovative coatings that functionalize the paper surfaces, together with advanced light management solutions (e.g. wave-optical light trapping structures and NIR-to-visible up-converters). These breakthroughs open the way for an innovative class of disposable opto-electronic products that can find widespread use and bring important added value to existing commercial products. By making these devices ubiquitous, flexible and conformable to any object or surface, will also allow them to become part of the core of the Internet of Things (IoT) revolution, which demands systems’ mobility and self-powering functionalities to satisfy the requirements of comfort and healthcare of the users. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnONPs) have received considerable attention as an antibacterial agent particularly in the textile industry. In the present work a successful procedure for in situ growth of ZnONPs in textiles was developed. The results obtained showed that a combination of in situ synthesis and the sol–gel method promoted a uniform and dense adsorption of the nanoparticles both inside and on the surface of fabric fibres. The fabrics finished with ZnONPs have been investigated for antibacterial properties by the agar diffusion method and by the absorption method according to the ISO 20743:2013 standard and exhibited an antibacterial effect against methicillin resistant Staphylococcus aureus ATCC33591, Staphylococcus epidermidis ATCC1228, Staphylococcus aureus RN4220 and Propionibacterium acnes ATCC6919. Moreover, tests conducted with hydrogen peroxide suggested the involvement of reactive oxygen species, namely the involvement of hydrogen peroxide, in the antibacterial activity of the zinc oxide nanoparticles. Therefore, the synthesised nanoparticles showed great potential to be used as coatings for medical, cosmetic or sports fabrics. [ABSTRACT FROM AUTHOR]

Dielectric-based photonic structures, composed of a lossless but high refractive index material, are currently among the preferential solutions for light management in thin film photovoltaics, as they allow broadband manipulation of sunlight to strongly boost the absorptance in the thin solar cell layers. In this work, we present an innovative colloidal lithography nanofabrication method that allows the precise engineering of wavelength-sized features, with the materials and geometries appropriate for efficient light trapping when implemented on the front surface of the cells. The method is developed here with TiO2 nanostructures tested on amorphous-silicon absorber thin films coated on the rear side by a metallic reflector. It is a simple, low-cost and scalable approach consisting of 4 main steps: (1) deposition of periodic close-packed arrays of polystyrene colloids which act as the mask; (2) shaping the particles and increasing their spacing via dry etching; (3) infiltration of TiO2 into the inter-particle spaces and (4) removal of the polystyrene particles to leave only the structured TiO2 layer. The resultant array of wavelength-sized features acts as a nanostructured high-index anti-reflection coating, which not only suppresses the reflected light at short wavelengths but also increases the optical path length of the longer wavelengths, via light scattering, within the absorber. The optical results have been compared with numerical electromagnetic computations to provide a deeper understanding of the physical mechanisms responsible for absorptance enhancement in the cells. A notorious 27.3% enhancement in the cell photocurrent is anticipated with the fabricated structures, relative to conventional anti-reflection coatings. [ABSTRACT FROM AUTHOR]

Solution-processed n-type oxide semiconductors have received great interest in thin-film transistor (TFT) applications. However, solution-processed p-type oxide semiconductors are not as successful as their n-type counterparts because of the lack of material choice and their complicated fabrication procedures. In this study, a simple one-step synthetic method was employed to fabricate a p-type Cu2O thin film via in-situ reaction of a CuI film in aqueous NaOH solution at room temperature. The structure, morphology, and component variations as a function of annealing conditions (≤350 °C) were investigated. The analysis indicates that the phase evolution of Cu2O → Cu2O + CuO → CuO occurred at higher temperatures and the pure CuO phase was achieved at 250 °C. The crystallinity, average grain size, and surface morphology of the CuxO thin films were found to increase in slope as the annealing temperature increased. To explore the possible applications of the obtained CuxO films as semiconducting channel components, bottom-gated TFTs on SiO2 gate dielectrics were constructed and examined. The hole mobility of the optimized device was calculated to be 0.32 cm2 V−1 s−1, along with an on/off current ratio of 5 × 104, and a subthreshold swing of 1.1 V dec−1. The further integration of the CuxO film on an Al2O3 high-k dielectric achieves an improved device performance at 2.5 V. This work successfully demonstrates a simple method to fabricate p-type Cu-based thin films and TFTs via a solution route, which represents a great step towards the development of low-cost and all-oxide complementary metal oxide semiconductor electronics. [ABSTRACT FROM AUTHOR]

The fabrication of water-induced amorphous high-k zirconium oxide (ZrOx) dielectrics has been proposed with the objective of achieving high performance and reducing costs for next generation displays. In this study, the as-prepared ZrOx thin films were fabricated by a sequential process, including a UV-assisted photochemical treatment and a thermal annealing process at temperatures lower than 300 °C. It is observed that the leakage current density of ZrOx thin films decreases, and the capacitance increases with increasing annealing temperatures. To verify the application possibilities of ZrOx thin films as gate dielectrics in complementary metal-oxide semiconductor (CMOS) electronics, both n-type In2O3 and p-type NiOx channel layers were integrated with ZrOx dielectrics and their corresponding electrical performances were examined. The In2O3/ZrOx thin film transistor (TFT) annealed at 250 °C exhibited a high electron mobility of 10.78 cm2 V−1 s−1, a small subthreshold swing of 75 mV dec−1, and a large on–off current ratio (Ion/Ioff) of around 106, respectively. Moreover, the p-type NiOx/ZrOx TFT exhibited an Ion/Ioff of 105 and a hole mobility of 4.8 cm2 V−1 s−1. It is noted that both n- and p-channel oxide TFTs on ZrOx could be operated at voltages lower than 4 V. The low-temperature fabrication process marks a great step towards the further development of low-cost, all-oxide CMOS electronics on flexible substrates. [ABSTRACT FROM AUTHOR]

Although there are a few research studies on solution-processed p-channel oxide thin-film transistors (TFTs), the strict fabrication conditions and the poor electrical properties have limited their applications in low-power complementary metal oxide semiconductor (CMOS) electronics. Here, the application of the polyol reduction method for processing p-type CuxO and NiOx channel layers and their implementation in TFT devices are reported. The optimized CuxO and NiOx TFTs were achieved at low annealing temperatures (∼300 °C) and exhibited decent electrical properties. Encouraged by the inspiring results obtained on SiO2/Si substrates, the TFT performance was further optimized by device engineering, employing high-k AlOx as the gate dielectric. The fully solution-processed NiOx/AlOx TFT could be operated at a low voltage of 3.5 V and exhibits a high hole mobility of around 25 cm2 V−1 s−1. Our work demonstrates the ability to grow high-quality p-type oxide films and devices via the polyol reduction method over large area substrates while at the same time it provides guidelines for further p-type oxide material and device improvements. [ABSTRACT FROM AUTHOR]

In this study, amorphous indium-tungsten oxide (IWO) semiconductor thin films were prepared by an eco-friendly spin-coating process using ethanol and water as solvents. The electrical properties of IWO thin-film transistors (TFTs), together with the structural and morphological characteristics of IWO thin films, were systematically investigated as functions of tungsten concentration and annealing temperature. The optimized IWO channel layer was then integrated on an aqueous aluminum oxide (AlOx) gate dielectric. It is observed that the solution-processed IWO/AlOx TFT presents high stability and improved characteristics, such as an on/off current ratio of 5 × 107, a field-effect mobility of 15.3 cm2 V−1 s−1, a small subthreshold slope of 68 mV dec−1, and a threshold voltage shift of 0.15 V under bias stress for 2 h. The IWO/AlOx TFT could be operated at a low voltage of 2 V, which was 15 times lower than that of conventional SiO2-based devices. The solution-processed IWO thin films synthesized in a green route would be promising candidates for large-area and high-performance low-cost devices. [ABSTRACT FROM AUTHOR]

Nowadays there is a strong demand for intelligent packaging to provide comfort, welfare and security to owners, vendors and consumers by allowing them to know the contents and interact with the goods. This is of particular relevance for low cost, fully disposable and recyclable products, such as identification tags and medical diagnostic tests, and devices for analysis and/or quality control in food and pharmaceutical industries. However, the increase of complexity and processing capacity requires continuous power and can be addressed by the combined use of a small disposable battery, charged by a disposable solar cell, which is able to work under indoor lighting. Herein, we show a proof-of-concept of the pioneering production of thin-film amorphous silicon (a-Si:H) solar cells with an efficiency of 4% by plasma enhanced chemical vapour deposition (PECVD) on liquid packaging cardboard (LPC), which is commonly used in the food and beverage industries. Such accomplishment put us one step closer to this revolution by providing a flexible, renewable and extremely cheap autonomous energy packaging system. Moreover, such Si thin films take advantage of their good performance at low-light levels, which also makes them highly desirable for cheap mobile indoor applications. [ABSTRACT FROM AUTHOR]

We report a sol–gel approach to fabricate aluminum oxyhydroxide (AlOOH)-based inks for the gravure printing of high-dielectric-constant nanocomposite films. By reacting 3-glycidoxypropyl-trimethoxysilane (GPTS) with aluminum oxyhydroxide (AlOOH) nanoparticles under constant bead milling, inks suitable for gravure printing were obtained. The calculated relative dielectric constants based on the measured capacitances and film thicknesses for the gravure-printed GPTS : AlOOH nanocomposites varied between 7 and 11 at a frequency of 10 kHz. The dielectric constant depended on the mixing ratio of the composite and was found to follow the Maxwell-Garnett ternary-system mixing rule, indicating the presence of micro/nanopores, which affect the electrical properties of the fabricated films. An increasing leakage current with increasing AlOOH content was observed. The high leakage current was reduced by printing two-layer films. The double-layered gravure-coated films exhibited a similar capacitance density, but a clearly lower leakage current and fewer electrical breakdowns compared to single-layered films with comparable film compositions and film thicknesses. The best composite yielded a capacitance density of 109 ± 2 pF mm−2 at 10 kHz frequency and a leakage current density of 60 ± 20 μA cm−2 at a 0.5 MV cm−1 electric field as a single layer. The calculated relative dielectric constant at 10 kHz frequency for this composition was 11.2 ± 0.5. [ABSTRACT FROM AUTHOR]

The development of flexible electronics has increased the demand for wearable pressure sensors that can be used to monitor various biomedical signals. In this context, pressure sensors based on zinc oxide (ZnO) have great potential since, besides the biocompatibility and biodegradability of this metal oxide, it also has piezoelectric properties. The common feature of these sensors is the alignment of the ZnO nanostructures in the strain direction. This alignment is achieved through a three-stage procedure: deposition of a ZnO nanoparticle layer (seed layer) followed by its patterning and the subsequent growth of nanostructures from the seed layer nanoparticles. Herein, a process compatible with industrial scale for depositing seed layers by flexographic printing is proposed, allowing seed layers to be deposited and patterned swiftly and efficiently in a single step on flexible indium tin oxide coated polyethylene terephthalate substrates, significantly decreasing the time and cost required to produce pressure sensors. The growth conditions of ZnO nanorods on these substrates were also studied to analyze their influence on the morphological and structural characteristics of the nanostructures. Nanorods with length of (0.27 ± 0.04) μm and density of (296 ± 6) nanorods per μm 2 were obtained in microwave-assisted hydrothermal syntheses carried out at 100 °C for 30 min, with a 1 M zinc acetate seed layer and using an equimolar growth solution of zinc nitrate and hexamethylenetetramine. These conditions were used to produce ZnO-based pressure sensors with two patterns (one square and 16 individual squares). Although the single square sensors displayed a higher average output voltage ((12 ± 5) V for an impact pressure of 150 kPa), their response was considerably more variable than the patterned sensors (with 16 squares), which displayed an average output voltage of (8 ± 2) V under an applied pressure of 150 kPa and sensitivity values of (0.06 ± 0.01) V kPa -1 , demonstrating their potential for wearables and portable electronics.

Solution based deposition has been recently considered as a viable option for low-cost flexible electronics. In this context, research efforts have been increasingly focused on the development of suitable solution-processed materials for oxide based transistors. In this work, we report a fully solution synthesis route, using 2-methoxyethanol as solvent, for the preparation of In 2 O 3 thin films and ZrO x gate dielectrics, as well as the fabrication of In 2 O 3 -based TFTs. To verify the possible applications of ZrO x thin films as the gate dielectric in complementary metal oxide semiconductor (CMOS) electronics, fully solution-induced In 2 O 3 TFTs based on ZrO 2 dielectrics have been integrated and investigated. The devices, with an optimized annealing temperature of 300 °C, have demonstrated high electrical performance and operational stability at a low voltage of 2 V, including a high μ sat of 4.42 cm 2 V -1 s -1 , low threshold voltage of 0.31 V, threshold voltage shift of 0.15 V under positive bias stress for 7200 s, and large I on / I off of 7.5 × 10 7 , respectively. The as-fabricated In 2 O 3 /ZrO x TFTs enable fully solution-derived oxide TFTs for potential application in portable and low-power consumption electronics., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Tuberculosis (TB) remains one of the most serious infectious diseases in the world and the rate of new cases continues to increase. The development of cheap and simple methodologies capable of identifying TB causing agents belonging to the Mycobacterium tuberculosis Complex (MTBC), at point-of-need, in particular in resource-poor countries where the main TB epidemics are observed, is of paramount relevance for the timely and effective diagnosis and management of patients. TB molecular diagnostics, aimed at reducing the time of laboratory diagnostics from weeks to days, still require specialised technical personnel and labour intensive methods. Recent nanotechnology-based systems have been proposed to circumvent these limitations. Here, we report on a paper-based platform capable of integrating a previously developed Au-nanoprobe based MTBC detection assay-we call it "Gold on Paper". The Au-nanoprobe assay is processed and developed on a wax-printed microplate paper platform, allowing unequivocal identification of MTBC members and can be performed without specialised laboratory equipment. Upon integration of this Au-nanoprobe colorimetric assay onto the 384-microplate, differential colour scrutiny may be captured and analysed with a generic "smartphone" device. This strategy uses the mobile device to digitalise the intensity of the colour associated with each colorimetric assay, perform a Red Green Blue (RGB) analysis and transfer relevant information to an off-site lab, thus allowing for efficient diagnostics. Integration of the GPS location metadata of every test image may add a new dimension of information, allowing for real-time epidemiologic data on MTBC identification.